Initiation and strain compatibility of connected extension twins in AZ31 magnesium alloy at high temperature

Journal Article · Thu Dec 15 04:00:00 EST 2016 · Materials Characterization

DOI:https://doi.org/10.1016/J.MATCHAR.2016.11.003· OSTI ID:22689676

Liu, Xiao ^[1]; Zhu, Biwu ^[1]; Huang, Guangjie ^[2]; Li, Luoxing ^[3]; Xie, Chao ^[4]; Tang, Changping ^[1]

---

1. Key Laboratory of High Temperature Wear Resistant Materials Preparation Technology of Hunan Province, Hunan University of Science and Technology, Xiangtan, Hunan 411201 (China)
2. College of Materials Science and Engineering, Chongqing University, Chongqing, Chongqing 400045 (China)
3. State Key Laboratory of Advanced Design and Manufacturing for Vehicle Body, Hunan University, Changsha, Hunan 410082 (China)
4. Faculty of Mechanical Engineering and Mechanics, Ningbo University, Ningbo 315211 (China)

Uniaxial compression tests were carried out at 350 °C and a strain rate of 0.3 s{sup −1} on as-extruded AZ31 magnesium alloy samples. At a true strain of − 0.1, extension twin pairs in a grain and twin chains across adjacent grains were detected. The orientation of selected twins and their host grains were determined by electron backscattered diffraction (EBSD) techniques. The Schmid factors (SFs), accommodation strains and geometric compatibility factors (m{sup ′}) were calculated. Analysis of the data indicated that the formation of twin pair and twin chain was related to the SF and m{sup ′}. Regarding to twin chain across adjacent grains, accommodation strain was also involved. The selection of twin variants in twin chain was generally determined by m{sup ′}. When the twins required the operation of pyramidal slip or twinning in adjacent grain, the corresponding connected twins with a relative high m{sup ′} were selected in this adjacent grain. - Highlights: •The formation of paired twins is studied during high temperature deformation. •The initiation of twinning in twin pair and twin chain obeys the Schmid law. •The twin variants' selection in twin chain is related to the geometric compatibility factor. •The accommodation strain plays an important role on the formation of twin chain.

• OSTI ID: 22689676
• Journal Information: Materials Characterization, Journal Name: Materials Characterization Vol. 122; ISSN 1044-5803; ISSN MACHEX
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
BACKSCATTERING
CHAINS
COMPATIBILITY
COMPRESSION
DEFORMATION
ELECTRON DIFFRACTION
GEOMETRY
MAGNESIUM ALLOYS
SLIP
STRAIN RATE
STRAINS
TEMPERATURE RANGE 0400-1000 K
TWINNING